Okay, here goes:
1. Deus Ex—Excellent, excellent game. The story is intriguing, and I love the characters (is Walton Simons THE bad-ass or is he?), the locations, the gadgets, the guns.. and all the choices you can make. Great bland of role-playing and fps. The graphics, AI and animation isn't the best, but who gives a damn. The atmosphere rocks and the game has cost me hours of hours of good night's sleep. I've probably played it through about seven or eight times, and the first time I got through it in about 80 hours. You do the math.
2. Hitman: Codename 47—I'll never get tired of whacking people in the first Hitman game. Ever. Lots of nice guns to play around with, smooth animations (motion capture guys did a nice job) and the supreme coolness of mr. Tobias Rieper AKA Codename 47 seals the deal. And when I'm tired of doing it the right way, I just enter the hotel or Lee Hong assasination levels packing like the Terminator, making it look like a bad day in Bosnia.
3. Arcanum: Of steamworks and magick obscura—A bit buggy, but still an excellent game. The first game I've played where it's actually possible to do everything (that includes running around the capital city naked and going to bed with a sheep, if you want to). I LOVE the possibilities in this game. You can be good, evil, smart, dumb, pretty, ugly, charismatic, manipulative, priest, thief, assassin, what ever. You choose which side you want to take, and the world reacts accordingly.
4. Fallout Tactics: Brotherhood of Steel—Take control of a squad of six highly trained soldiers armed to the teeth and wreak havoc on raiders and mutants in the post-nuclear US of A. The atmosphere in this game is so good, it really captures that dystopian, post-apocalyptic feeling. Delightful humor and an insane arsenal of weapons and gadgets.. a winner.
5. Aliens vs. Predator—This game has scared the piñatas out of me more times than I can count. That uneasy feeling you get when starting the first level as a marine is undescribable. Also, there is great joy in playing the highly intelligent and bloodthirsty alien, scaring the living hell out of marines and civilians alike, eating them alive. Also, the Pred campaign offers a great deal of excitement, massacring humans and battling aliens. I've also had hours of fun playing on a LAN with and against my friends.. a great game indeed.
6. Cythera—The game that introduced me to the wonderful world of Ambrosia Software. Cythera is a jewel of a game that you can really lose yourself into. Really neat, and it pains me that we'll probably never see an editor for it. And if we do, I'd probably not understand it with my simple mind and all
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Cythera has made me linger here for years now, and I remember when this board had more activity.. quite a shame that it has come to this, actually. I remember the team stories, how Cythera encouraged me to write chronicles and post them here.. heh, I even remember when Avatara had a post count of 400
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come to think of it, I have quite a few nice memories from this place..
7. The Sims—And the expansions (except Makin' Magic, which totally screwed the original idea of the game). Not so much because of the gameplay, because that becomes very linear and boring very fast. No, what I enjoy the most is designing houses, rooms, characters and their personalities and backgrounds. I've sat countless hours on the Net downloading silly little pieces of furniture, appliances, wallpapers, skins and the like.. I think the game's loading time came close to 10 minutes because of all the extra stuff I downloaded. Mind you, it was a slow computer.. but still!
8. Command&Conquer: Red Alert—A good, old game that I grew up with, still entertaining and challenging today. Oh, the satisfaction of cruching the opposition with my giant war machine.. the satisfaction of having an army of allied cruisers flattening the Soviet base without mercy.. the satisfaction of capturing the enemy structures, being able to build every unit in the game and totally ruling the skirmish-mode battlefield.. damn, I feel like playing it right now!
9. Soldier of Fortune—It's gory, it's simple, it's delightful. A great arsenal of badass weapons and plenty of terrorists to shoot. It doesn't get much easier—or better—than that, really. A great game to play if you've had a bad day and need to take it out on something. Especially entertaining to play if you've been playing some heavy-duty strategy game for too long and need to unwind with something simple. I'll never get tired of this game.
10. The Marathon trilogy—I had lots of fun with these games as a "kid". When I was first introduced to Marathon, I thought it was the epitome of coolness. And I really enjoy the story, too. I wonder if they're ever going to make a movie out of this (just let it be a talented director and not some piece of llama dung like Paul W. S. Anderson). I recently re-discovered the trilogy (now abandonware) and decided to play through it for the first time (it was hard to obtain all those years ago, me being pretty young and living in Norway, so all I had at that time was the demos, which I played over and over. I actually played it against my mom, too, which was quite entertaining)
That's it for now. But I really hope that I can add F.E.A.R. and Alan Wake to that list.. they look really promising.. time will show. Oh, and Morrowind. I own a copy of the game, but my good for nothing PC isn't strong enough
Honorable mentions goes out to Max Payne, Half-Life, Clive Barker's Undying, Age of Empires II: The Age of Kings, Escape Velocity, EV: Nova and Delta Force II. Good games that unfortunately didn't make the cut.